1. Field of the invention
The present invention relates to electrical connectors, especially to a card connector provided for electrically connecting a card to a circuit board.
2. Description of Related Art
In electronic appliances, such as portable telephones, PDA, digital cameras and the like, addition of a variety of functions and identification of a user are achieved by inserting an IC card with a built-in IC, such as a SIM (subscriber identify module) card, an MMC (multimedia card), an SD (secure digital or super density) card, an MS (memory stick) card and the like therein. Such an IC card is usually connected to the circuit board via a card connector.
The IC card of this kind normally has some means for inhibiting the write operation in order to protect information stored in its internal memory. A means is also provided to cancel the write protection to allow information to be written from an electronic device into the memory of the IC card. In order to contact or cut electrically between IC card and the electronic device accurately and conveniently, the card connector commonly equips with switches to achieve above-mentioned object.
U.S. Pat. No. 6,135,809 shows a conventional card connector comprising an insulative housing, a plurality of terminals retained in the housing, and a detecting device positioned on one side of the housing for detecting of a card. The housing defines a main body and a pair of sidewalls parallel to each other and extending forwards from two opposite sides of the main body and defining a receiving space therebetween for receiving an IC card therein. The main body defines a plurality of passageways therethrough for receiving corresponding terminals therein. The detecting device is engaged with one side of the housing for detecting the IC card out and comprises a first piece of metal made from a stationary piece of metal having a first contacting portion; and a second piece of metal having a second contacting portion, the first and second contacting portions can come in contact with each other before the IC card is inserted into the receiving space of the housing. At this time, the IC card is on a protect-on position (write inhibit position). The first and second contacting portions can separate from each other when the IC card is completely inserted into the receiving space of the housing. At this time, the IC card is on a protect-off position (write enable position).
However, because the first piece meets with the second piece simply to connect each other, dust and other matter residing on both of communication portions thereof cannot be cleared automatically so that the connecting performance is not reliable. Furthermore, when the IC card is detected or inserted manually frequently, fingers of users' are easy to touch the first and second contacting portions of corresponding pieces thereby reducing conductivity of the detecting device or damaging the detecting device.
Therefore, an improved card connector is desired to overcome the disadvantages of the prior arts.